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Random access: PDSCH with UE contention resolution identity (MSG4)V15.11.0

In response to a PUSCH transmission scheduled by a RAR UL grant when a UE has not been provided a C-RNTI, the UE attempts to detect a DCI format 1_0 with CRC scrambled by a corresponding TC-RNTI scheduling a PDSCH that includes a UE contention resolution identity (TS 38.321).

In response to the PDSCH reception with the UE contention resolution identity, the UE transmits HARQ-ACK information in a PUCCH. The PUCCH transmission is within a same active UL BWP as the PUSCH transmission.

A minimum time between the last symbol of the PDSCH reception and the first symbol of the corresponding PUCCH transmission with the HARQ-ACK information is equal to NT,1 + 0.5 msec. NT,1 is a time duration of N1 symbols corresponding to a PDSCH processing time for UE processing capability 1 when additional PDSCH DM-RS is configured. N1 = {14, 13, 20, 24} for μ = {0, 1, 2, 3}.

When detecting a DCI format in response to a PUSCH transmission scheduled by a RAR UL grant, or corresponding PUSCH retransmission scheduled by a DCI format 0_0 with CRC scrambled by a TCRNTI provided in the corresponding RAR message, the UE may assume the PDCCH carrying the DCI format has the same DM-RS antenna port quasi co-location properties as for a SS/PBCH block the UE used for PRACH association, regardless of whether or not the UE is provided TCI-State for the CORESET where the UE receives the PDCCH with the DCI format.

contention resolutionContention resolution